Abstract: An image decoding apparatus including a header decoder configured to decode, from coded data, a flag indicating whether dependent quantization is enabled and a flag prohibiting transform skip residual quantization, and a TU decoder configured to decode a transform coefficient in a TU block in an RRC mode in which a LAST position is coded, the LAST position corresponding to a decoding start position for the transform coefficient, or a TSRC mode in which the LAST position is not coded. The TU decoder performs dependent quantization in the RRC mode in a case that the transform coefficient for transform skip is decoded in the TSRC mode, and does not perform dependent quantization in the RRC mode in a case that the transform coefficient for transform skip is decoded in the RRC mode.

Abstract: The amount of memory required for CCLM prediction is reduced. The CCLM prediction parameter derivation unit (310442) derives a scale shift value corresponding to a luma difference value, and derives a CCLM prediction parameter, by shifting, by using the scale shift value, a value obtained by multiplying a value of a table referred to with a value obtained by performing right shift of the luma difference value by the scale shift value as an index and a chroma difference value. In addition, in a case of deriving a prediction image, a bit width is reduced by adaptively deriving a shift amount of a linear prediction parameter from the chroma difference value.

Abstract: A 3D data decoding apparatus for decoding encoded data includes a mesh prediction unit configured to derive a prediction position of a base mesh vertex position from the encoded data, and an arithmetic decoder configured to arithmetically decode a prediction residual. The arithmetic decoder decodes a part of a beginning of a prefix of an absolute value of a coefficient of the prediction residual by using a context and adds the prediction position and the prediction residual to derive the base mesh vertex position.

Abstract: A load in processing of searching for a motion vector is reduced. In order to solve the problem described above, a motion vector derivation apparatus according to one aspect of the present invention that derives a motion vector to be referred to for generating a prediction image to be used for coding or decoding of a video includes a motion vector search unit configured to search for a motion vector on a prediction unit basis through matching processing. The motion vector search unit is configured to stop search of the motion vector, depending on whether or not a conditional expression according to a pixel bit-depth is satisfied.

Abstract: A 3D data decoding apparatus for decoding encoded data includes an arithmetic decoder configured to arithmetically decode a mesh displacement from the encoded data. The arithmetic decoder decodes a part of a beginning of a prefix of a remainder of an absolute value of a coefficient of the mesh displacement by using a context.

Abstract: A 3D data decoding apparatus includes a geometry decoder configured to decode a geometry frame from encoded data, an attribute decoder configured to decode an attribute frame from the encoded data, a refinement information decoder configured to decode refinement characteristics information and refinement activation information from the encoded data, and a refinement processing unit configured to perform refinement processing on the attribute frame or the geometry frame according to the refinement characteristics information. The 3D data decoding apparatus further includes a syntax element indicating a number of refinements is decoded from the refinement activation information and an index indicating the refinement characteristics information for the decoded number of refinements is decoded.

Abstract: A video decoding apparatus includes an image decoding apparatus configured to decode coded data and generate a decoded image, a supplemental enhancement processing apparatus configured to perform supplemental enhancement processing on the decoded image, and a supplemental enhancement information decoding apparatus configured to decode multiple pieces of supplemental enhancement information for causing the supplemental enhancement processing apparatus to operate. The multiple pieces of supplemental enhancement information includes a piece of supplemental enhancement information indicating a priority processing order of the multiple pieces of supplemental enhancement information. The piece of supplemental enhancement information includes information further indicates a change of a parameter of the decoded image to be input to the supplemental enhancement processing apparatus based on the priority processing order.

Abstract: A problem with known SEI is that a relationship between a target image and an input tensor of a neural network model and a relationship between an output tensor and an output image are undefined or insufficient, and thus processing cannot be performed by simply using a model. Another problem is that in a case that the color component of the output image and the color component of the target image are different from each other, processing cannot be performed. An aspect of the present invention provides a video decoding apparatus including a prediction image derivation unit configured to decode a prediction image, and a residual decoder configured to decode a residual, wherein an input tensor is derived from a parameter indicating the number of channels of the input tensor and the output tensor of the neural network model or an image is derived from the output tensor.

Abstract: Provided is a video decoding apparatus for decoding coded data of a tile group in which a picture is split into rectangular regions, the tile group being composed of segments, the video decoding apparatus including: a header decoder configured to decode the number of tiles, a WPP enabled flag, and a slice enabled flag indicating whether segments in a target tile group are rectangular tiles, CTU rows, or slices from a tile group header, wherein the header decoder is configured to decode only one of the number of tiles being two or more, the WPP enabled flag being 1, and the slice enabled flag being 1 in one tile group.

Abstract: Complexity of coding/decoding of a video is reduced. An image decoding apparatus (31) includes a CN information decoder (10) configured to hierarchically split a coding node by at least any of binary tree split and ternary tree split. The CN information decoder refers to a method of splitting an immediately higher node, which is a node one generation higher than a target node, to restrict a method of splitting the target node.

Abstract: A video coding/decoding apparatus that can enhance coding efficiency using non-separable transform is provided. A video decoding apparatus according to an aspect of the present invention includes a prediction image generation unit configured to generate a prediction image, and an inverse non-separable transform processing unit configured to perform inverse non-separable transform. The non-separable transform processing unit does not change a specific frequency component of a transform coefficient.

Abstract: Object A video coding and decoding apparatus that can enhance coding efficiency is provided. Solution A video decoding apparatus includes an OOB determination unit configured to determine whether a reference block is a target of OOB processing by comparing coordinates of the reference block with coordinates of a picture, and an OOB mask derivation unit configured to derive mask data indicating whether a pixel is available by comparing coordinates of the pixel included in the reference block with the coordinates of the picture. The OOB determination unit determines whether the reference block is the target of the OOB processing based on presence or absence of processing to be applied to a reference picture including the reference block.

Abstract: A load in processing of searching for a motion vector is reduced. In order to solve the problem described above, a motion vector derivation apparatus according to one aspect of the present invention that derives a motion vector to be referred to for generating a prediction image to be used for coding or decoding of a video includes a motion vector search unit configured to search for a motion vector on a prediction unit basis through matching processing. The motion vector search unit is configured to stop search of the motion vector, depending on whether or not a conditional expression according to a pixel bit-depth is satisfied.

Abstract: A 3D data decoding apparatus for decoding coded data. The 3D data decoding apparatus includes an arithmetic decoder configured to arithmetically decode mesh displacement from the coded data, a context selection unit configured to select a context in the arithmetic decoding, and a context initialization unit configured to set an initial value of the context. In the context initialization unit, a context initialization parameter for initializing the context is decoded from the coded data.

Abstract: Video coding and decoding apparatuses that can enhance coding efficiency are provided. A video decoding apparatus according to an aspect of the present invention is a video decoding apparatus including a parameter decoder configured to decode, from coded data, syntax (mts_idx) of a target block. The parameter decoder decodes mts_idx depending on a block size, a LAST position, and a non-zero coefficient position of the target block. The parameter decoder determines whether to decode mts_idx, using a threshold for the LAST position. The threshold is larger in a case that the block size is equal to or larger than a prescribed size than in a case that the block size is smaller than the prescribed size.

Abstract: A video decoding apparatus is a video decoding apparatus for deriving a prediction image by using a reference picture included in a reference picture list.

Abstract: An arithmetic coding scheme is provided for coding and decoding 3D data and improves coding efficiency for mesh displacements and high-quality coding, and decoding of the 3D data. A 3D data decoding apparatus is also provided for decoding coded data. The apparatus contains an arithmetic decoder that is configured to arithmetically decode a mesh displacement from the coded data. The arithmetic decoder decodes, from the coded data, a first flag indicating whether a coefficient of the mesh displacement has an absolute value greater than 0, a second flag indicating whether the coefficient has an absolute value greater than 1, and a third flag indicating whether the coefficient has an absolute value greater than 2.

Abstract: Provided is a video decoding apparatus for decoding coded data of a tile group in which a picture is split into rectangular regions, the tile group being composed of segments, the video decoding apparatus including: a header decoder configured to decode the number of tiles, a WPP enabled flag, and a slice enabled flag indicating whether segments in a target tile group are rectangular tiles, CTU rows, or slices from a tile group header, wherein the header decoder is configured to decode only one of the number of tiles being two or more, the WPP enabled flag being 1, and the slice enabled flag being 1 in one tile group.

Abstract: A video coding scheme for encoding and decoding 3D data encodes and decodes a mesh displacement image as an image in a 4:2:0 format, reduces distortion caused by encoding, and encodes and decodes 3D data with high quality. A 3D data decoding apparatus includes a video decoder that is configured to decode a mesh displacement image decoded from a geometry video stream in which a Unit Type of coded data is V3C_GVD and a displacement unmapper that is configured to derive a mesh displacement per position pos and component compIdx from the mesh displacement image. The displacement unmapper is further configured to derive a Y coordinate of a geometry image from a product of a height and a variable from 0 to a value indicating a number of dimensions of geometry minus 1 to derive the mesh displacement in a case that the geometry image is in a 4:2:0 format.

Abstract: In a case that all network parameters are adaptively switched, it is difficult to switch the parameters for each small block, such as a CTU. There is a problem in that, in a case that ALF class classification and filtering are successively performed in ALF parallel after application of an NN filter, processing requires time. By selecting an NN model in a slice header and selecting a network layer finetuned in a CTU, the NN model can be adaptively selected even for each small block. By performing ALF class classification in an image before being subjected to an NN filter and performing ALF processing using an image subjected to NN filtering processing and ALF class information, the NN filtering processing and the ALF class classification can be performed in parallel.